We've reached 1969 and this mixed series continues (thank God for The Invasion). This is another story with great potential which ultimately doesn't work.

The first episode and a half is mostly entertaining, if a bit slow. I enjoyed the concept of the most intelligent members of the community on this (unnamed) planet being taken away on a regular basis (we are never told how often - every day, every month?) as part of a "self-perpetuating slavery". I also enjoyed The Doctor's explanation of the human race coming from a kind of "genetic soup" in the sea and inferring that these aliens had developed on this planet from "a different kind of soup".

Before the Krotons are revealed we see different disembodied alien features throughout the episodes, this was effective and gave the enemies an individual feel. If they had kept this up of the four episodes I think I would have a very different view of this story.

Once revealed in their entirety the Krotons are disappointing generic "robot baddies" with no real character or substance. Doctor Who is at its worst when it tries to summon a robot enemy without putting any thought into what makes these creatures different or interesting. In all honesty I can't tell you what separates these creatures from Quarks or War Machines - why should I care about them? What makes them tick?

Similarly, I don't care much about any of the stories' characters. In that respect it is a world away from The Invasion and unbearably similar to The Dominators (how did they end up in the same series?!). Just like The Dominators there is a race of almost annoyingly placid individuals with the exception of one man who is not afraid to speak out (in both cases a relation to a high ranking official - yawn). The population seem uninterested in taking any kind of action to stop themselves from being completely controlled by an unseen force. In fairness, there is greater explanation surrounding the Kroton's power over the Gonds actions than in this other season six story (general mind control).

By the time we got to the point in the story where the Krotons reveal their entire plan in full to The Doctor I'd lost interest. This exposition didn't feature anything that wasn't immediately obvious from watching the previous three episodes.

Thank God this wasn't an 8 part story, eh?